A panel is a collection of recruited individuals who agree to the collection of data related to some aspect of their behavior, usually in return for compensation. Panels may be used for a single media outlet, such as over-the-air broadcast television program viewing, product purchases, and Internet Web browsing. A single source panel (SSP) may combine many different behavioral aspects.
Careful selection of panelists is an important aspect of panel creation. Ideally a panel creator would be able to verify the identity of each panelist. This is so because the panel may be designed to evaluate behavioral aspects of different demographic groups within the larger population of which the panel is a sample. A panel may be designed to have X panelists with demographics A; panelists with demographics B; and Z panelists with demographics C. The accuracy and value of panel results are tied directly to how accurately the actual panel demographics match the panel design demographics.
Furthermore, a panel creator may find that recruiting panelists with demographics C is much harder than those with demographics A, and thus the panel creator may feel compelled to offer greater incentives to potential panelists with demographics C than those with demographics A. Knowing this, potential panelists with demographics A may provide false information to the panel creator so as to obtain the greater incentives.